OldGeek:
I still don't understand how anything connected to the Orcon device over LAN (or Wi-Fi for that matter) can bring down the Orcon device.
It's possible for a device to be sending malformed packets (for whatever reason) that can cause another device to crash when they receive something unexpected.
A pretty bad analogy would be a faulty washing machine (the orbi) causing a circuit breaker to trip on the switchboard (Orcon router). A fault in one place has an effect somewhere else.
Not saying that is definitely your problem, but it's a pretty reasonable troubleshooting step to try. You won't know unless you try it.